Cardiac autonomic imaging with SPECT tracers

Anthracycline-induced cardiomyopathy: The search continues

“…Recent reviews have summarized the mechanism by which I-123 MIBG is taken up by the nerve terminal, the utility of this agent, and the technical aspects of its imaging. [24][25][26][27] One of the strengths of the current study by dos Santos 28 is that all of the subjects were relatively young (mean age of 16), when identification of early anthracycline-induced cardiomyopathy would be most critical. The subjects were a median of 5.3 years out from their chemotherapy.…”

123I-mIBG: Simplicity and reproducibility

“…3 Specific to the cardiac uses of this agent, it provides insight into the myocardial sympathetic nervous system and its impact of different disease states. 4 The myocardial uptake of these agents was first described in canine subjects in 1980 5 and in human subjects in 1981. 6 Clinical applications of these agents have expanded rapidly.…”

“…Despite these differences, all three techniques have lead to similar results. 4 In response to several calls to standardize the technique, 13,14 a standardization proposal by the European Association of Nuclear Medicine and the European Council of Nuclear Cardiology was developed. 15 This called for the H/M ratio to be determined using the average counts per pixel in a myocardial region of interest to the average counts per pixel in the mediastinum (excluding the thyroid).…”

“…Regional assessment of tracer uptake has been described, but regional differences in uptake (even among healthy subjects) and frequent lack of acceptable image quality have limited clinical applications of this technique. 4,20 Lung uptake of mIBG has also been evaluated for its prognostic value in patients with heart failure with reduced ejection fraction. 21,22 Kamiyoshi et al reported that the lung/heart ratio was found to be an independent predictor of cardiac events.…”

It’s not all in the numbers

“…36,37 A nuclear cardiology technique studied for many years, but only recently gaining clinical interest in the US, is assessment of cardiac sympathetic adrenergic innervation using analogs of the sympathetic mediator norepinephrine, mostly the SPECT tracer iodine 123 meta-iodobenzylguanidine ( 123 I-mIBG), but also PET tracers such as C-11 hydroxyephedrine ( 11 C-HED). 38,39 Soon after the initial report of human cardiac imaging with 123 I-mIBG, 40 the first systematic study of patients with cardiac disease proposed use of a quantitative heart to mediastinal ratio (HMR) on an anterior planar image, and showed correlation of HMR with LVEF in patients with cardiomyopathy. 41 Shortly thereafter, the first study showing prognostic utility of 123 I-mIBG imaging in advanced heart failure (HF) analyzed 123 I-mIBG images in terms of the quantitative HMR, finding this value to be more ''potent'' than other parameters, including LVEF, in predicting death.…”